Sign up to receive free email alerts when patent applications with chosen keywords are publishedSIGN UP

Abstract:

The present invention discloses a method and enabling apparatus for
integrating a new fuel or fuels into an operating transportation system
in a continuous, seamless manner. The method disclosed overcomes the
economic risk associated with developing a new fuel when there is little
or no fuel distribution infrastructure in place for the new fuel.
Integrating a new fuel into an existing transportation system can be
implemented with two enabling technologies. The first is an engine
capable of operating seamlessly on multiple fuels. The second is a system
of determining a driving strategy that makes the transition from one fuel
to another seamless to the driver. A compact, high-performance gas
turbine engine is an enabling apparatus of the above strategy. The system
of driving strategy disclosed herein allows the operator of the vehicle
or the fleet manager to minimize operational costs by estimating the best
combination of fuels, fuel dispensers and driving strategies. By carrying
at least one readily available fuel, the operator is free of
infrastructure shortcomings for other fuels that may be less expensive or
have superior emissions characteristics. The vehicle operator can
therefore efficiently manage the use of on-board fuels as well as
efficiently manage the driving schedule and route to achieve the lowest
overall operating costs.

Claims:

1. A method, comprising: (a) determining, by a computer, a current
spatial location of a vehicle, the vehicle having at least differing
first and second fuels for a common engine of the vehicle; (b)
determining, by the computer, at least one of fuel availability, fuel
pricing information and routing information for one or more fuel
dispensers within a determined range of the vehicle; and (c) based on the
determined at least one of fuel availability, fuel pricing information
and routing information, determining, by the computer, a fuel strategy
involving at least one of the first and second fuels.

2. The method of claim 1, wherein the current location is received from a
satellite positioning system and further comprising: (d) determining at
least one of current fuel and engine information for the vehicle, wherein
the fuel strategy is based on the determined at least one of current fuel
and engine information for the vehicle.

3. The method of claim 2, wherein the at least one of current fuel and
engine information is current fuel information and comprises a type and
amount of fuel in each of first and second fuel tanks of the vehicle,
which of the first and second fuels are currently being fed into the
engine of the vehicle, a current fuel consumption rate of the engine, and
a current injection fuel mixture being fed to the engine.

4. The method of claim 2, wherein the at least one of current fuel and
engine information is current engine information and comprises current
engine temperature, current engine fuel/air ratio, current engine oil
pressure, current vehicle velocity and/or acceleration, and current
engine power output.

5. The method of claim 1, wherein the at least one of fuel and pricing
information for one or more fuel dispensers comprises one or more of
current price for one or more fuels offered by each one or more fuel
dispensers, identity and/or location of each one or more fuel dispensers,
hours of business and/or products and/or amenities offered by each one or
more fuel dispensers, for each one or more fuel dispenser available fuel
types and/or fuel replacement cost, directions from the current vehicle
location to each one or more fuel dispensers, and a respective link to a
web page of each one or more fuel dispensers.

6. The method of claim 1, wherein the determined fuel strategy is based
in part on an applicable emission requirement.

7. The method of claim 1, wherein the determined fuel strategy comprises
one or more of the following: (i) which of the first and second fuels
will be combusted by the engine; (ii) a fuel/air ratio to be combusted by
the engine; (iii) a mixture of the first and second fuels to be combusted
by the engine; (iv) an engine setting for the engine; (v) an identity
and/or location of a fuel dispenser to be used by the operator; (vi) a
fuel specific energy content; and (vii) a fuel ignition characteristic to
be employed.

10. A system, comprising: a computer operable to: (a) determine a current
spatial location of a vehicle, the vehicle having at least differing
first and second fuels for a common engine of the vehicle; (b) determine
at least one of fuel and pricing information for one or more fuel
dispensers within a determined range of the vehicle; and (c) based on the
determined at least one of fuel and pricing information, determine a fuel
strategy involving at least one of the first and second fuels.

11. The system of claim 10, wherein the current location is received from
a satellite positioning system and wherein the computer is further
operable to: (d) determine at least one of current fuel and engine
information for the vehicle, wherein the fuel strategy is based on the
determined at least one of current fuel and engine information for the
vehicle.

12. The system of claim 11, wherein the at least one of current fuel and
engine information is current fuel information and comprises a type and
amount of fuel in each of first and second fuel tanks of the vehicle,
which of the first and second fuels are currently being fed into the
engine of the vehicle, a current fuel consumption rate of the engine, and
a current injection fuel mixture being fed to the engine.

13. The system of claim 11, wherein the at least one of current fuel and
engine information is current engine information and comprises current
engine temperature, current engine fuel/air ratio, current engine oil
pressure, current vehicle velocity and/or acceleration, and current
engine power output.

14. The system of claim 10, wherein the at least one of fuel and pricing
information for one or more fuel dispensers comprises one or more of
current price for one or more fuels offered by each one or more fuel
dispensers, identity and/or location of each one or more fuel dispensers,
hours of business and/or products and/or amenities offered by each one or
more fuel dispensers, for each one or more fuel dispenser available fuel
types and/or fuel replacement cost, directions from the current vehicle
location to each one or more fuel dispensers, and a respective link to a
web page of each one or more fuel dispensers.

15. The system of claim 10, wherein the determined fuel strategy is based
in part on an applicable emission requirement.

16. The system of claim 10, wherein the determined fuel strategy
comprises one or more of the following: which of the first and second
fuels will be combusted by the engine; a fuel/air ratio to be combusted
by the engine; a mixture of the first and second fuels to be combusted by
the engine; an engine setting for the engine; an identity and/or location
of a fuel dispenser to be used by the operator; and a fuel specific
energy content to be employed.

17. The system of claim 10, further comprising: implementing the
determined fuel strategy, wherein implementing requires changing a fuel
type and/or mixture being provided to the engine.

18. A method, comprising: (a) determining, by a computer, a current
spatial location of a vehicle comprising a fuel; (b) determining, by the
computer, a plurality of fuel dispensers within a determined range of the
current vehicle location; (c) for each fuel dispenser, determining, by
the computer, at least one of a price for the fuel, a fuel consumption,
and a cost to drive to the respective fuel dispenser from the current
vehicle location; and (d) presenting, by a computer and to the operator,
at least one of the fuel price, the fuel consumption, the driving cost, a
recommendation of a fuel dispenser of the plurality of fuel dispensers,
and a ranking of at least some of the plurality of fuel dispensers.

19. The method of claim 18, wherein the determining step (a) comprises
receiving the current spatial location from a satellite positioning
system.

20. The method of claim 18, wherein the at least one of a price for the
fuel and a cost to drive to the respective fuel dispenser from the
current vehicle location in step (c) is the fuel price.

21. The method of claim 18, wherein the at least one of a price for the
fuel and a cost to drive to the respective fuel dispenser from the
current vehicle location in step (c) is the cost.

22. The method of claim 18, wherein the at least one of the fuel price,
driving cost, a recommendation of a fuel dispenser of the plurality of
fuel dispensers, and a ranking of at least some of the plurality of fuel
dispensers is fuel price.

23. The method of claim 18, wherein the at least one of the fuel price,
driving cost, a recommendation of a fuel dispenser of the plurality of
fuel dispensers, and a ranking of at least some of the plurality of fuel
dispensers is driving cost.

24. The method of claim 18, wherein the at least one of the fuel price,
driving cost, a recommendation of a fuel dispenser of the plurality of
fuel dispensers, and a ranking of at least some of the plurality of fuel
dispensers is the recommendation.

25. The method of claim 18, wherein the at least one of the fuel price,
driving cost, a recommendation of a fuel dispenser of the plurality of
fuel dispensers, and a ranking of at least some of the plurality of fuel
dispensers is the ranking

26. A vehicle, comprising: a first fuel in a first fuel tank, the first
fuel having an octane rating ranging from about 60 to about 120; a first
fuel in a first fuel tank, the first fuel having a specific energy,
expressed as a low heat value, ranging from about 10 million joules per
kilogram to about 60 million joules per kilogram; a second fuel in a
second fuel tank, the second fuel having a cetane number from about 10 to
about 100; a second fuel in a second fuel tank, the second fuel having a
specific energy, expressed as a low heat value, ranging from about 10
million joules per kilogram to about 60 million joules per kilogram; one
of a turbine and microturbine engine; and a fuel injection system
operable to provide selectively to the engine the first fuel in the
substantial absence of the second fuel, the second fuel in the
substantial absence of the first fuel, and a mixture of the first and
second fuels.

27. The vehicle of claim 26, wherein the first and second fuels are each
substantially free of octane enhancers and cetane improvers.

28. The vehicle of claim 26, wherein the first and second fuels primarily
include a hydrocarbon other than propane and methane.

29. A vehicle, comprising: a first fuel in a first fuel tank; a second
fuel in a second fuel tank, the first and second fuels having differing
compositions; one of a turbine and microturbine engine; and a fuel
injection system operable to provide selectively to the engine the first
fuel in the substantial absence of the second fuel, the second fuel in
the substantial absence of the first fuel, and a mixture of the first and
second fuels, wherein at least one of the following is true: (a) a volume
of the second fuel tank to the volume of the first fuel tank is in the
range of from about 0.3:1 to about 1:1; and (b) an available fuel energy
of the first fuel in the first fuel tank to the second fuel in the second
fuel tank is in the range of from about 2.5:1 to about 10:1.

30. The vehicle of claim 29, wherein (a) is true.

31. The vehicle of claim 29, wherein (b) is true.

32. The vehicle of claim 29, wherein the first fuel is at least one of
diesel fuel, gasoline and LNG and the second fuel is at least one of CNG,
propane, butane and hydrogen.

33. A method, comprising: (a) providing a vehicle, the vehicle carrying
first and second fuels, the first fuel being commonly available and the
second fuel not being as commonly available as the first fuel and wherein
a fuel injection system can provide selectively to a common engine at
least one of a selected one of the first and second fuels and a selected
combination of the first and second fuels; (b) determining, by a
processor-executable on-board satellite positioning module, a current
spatial location of the vehicle; (c) determining, by the processor, at
least one of fuel and pricing information for one or more fuel dispensers
within a determined range of the vehicle; and (d) based on the determined
at least one of fuel and pricing information, determining, by the
processor, a fuel strategy involving at least one of the first and second
fuels.

34. The method of claim 33, further comprising: determining at least one
of current fuel and engine information for the vehicle, wherein the fuel
strategy is based on the determined at least one of current fuel and
engine information for the vehicle.

35. The method of claim 34, wherein the at least one of current fuel and
engine information is current fuel information and comprises a type and
amount of fuel in each of first and second fuel tanks of the vehicle,
which of the first and second fuels are currently being fed into the
engine of the vehicle, a current fuel consumption rate of the engine, and
a current injection fuel mixture being fed to the engine.

36. The method of claim 34, wherein the at least one of current fuel and
engine information is current engine information and comprises current
engine temperature, current engine revolutions per minute, current engine
oil pressure, current vehicle velocity and/or acceleration, and current
engine power output.

37. The method of claim 33, wherein the at least one of fuel and pricing
information for one or more fuel dispensers comprises one or more of
current price for one or more fuels offered by each one or more fuel
dispensers, identity and/or location of each one or more fuel dispensers,
hours of business and/or products and/or amenities offered by each one or
more fuel dispensers, for each one or more fuel dispenser available fuel
types and/or fuel replacement cost, directions from the current vehicle
location to each one or more fuel dispensers, and a respective link to a
web page of each one or more fuel dispensers.

38. The method of claim 33, wherein the determined fuel strategy is based
in part on an applicable emission requirement.

39. The method of claim 33, wherein the determined fuel strategy
comprises one or more of the following: (i) which of the first and second
fuels will be combusted by the engine; (ii) a fuel/air ratio to be
combusted by the engine; (iii) a mixture of the first and second fuels to
be combusted by the engine; (iv) an engine setting for the engine; (v) an
identity and/or location of a fuel dispenser to be used by the operator;
(vi) a fuel specific energy content; and (vii) a fuel ignition
characteristic to be employed.

42. A system, comprising: a processor operable to: determine a current
spatial location of the vehicle, the vehicle comprising a commonly
available first fuel and a less commonly available second fuel, a common
engine, and a fuel injection system to provide selectively to the engine
a selected one of the first and second fuels; and a processor operable
to: determine at least one of fuel and pricing information for one or
more fuel dispensers within a determined range of the vehicle; and based
on the determined at least one of fuel and pricing information, determine
a fuel strategy involving at least one of the first and second fuels.

43. The system of claim 42, wherein the processor is further operable to
determine at least one of current fuel and engine information for the
vehicle, wherein the fuel strategy is based on the determined at least
one of current fuel and engine information for the vehicle.

44. The method of claim 43, wherein the at least one of current fuel and
engine information is current fuel information and comprises a type and
amount of fuel in each of first and second fuel tanks of the vehicle,
which of the first and second fuels are currently being fed into the
engine of the vehicle, a current fuel consumption rate of the engine, and
a current injection fuel mixture being fed to the engine.

45. The system of claim 43, wherein the at least one of current fuel and
engine information is current engine information and comprises current
engine temperature, current engine revolutions per minute, current engine
oil pressure, current vehicle velocity and/or acceleration, and current
engine power output.

46. The system of claim 42, wherein the at least one of fuel and pricing
information for one or more fuel dispensers comprises one or more of
current price for one or more fuels offered by each one or more fuel
dispensers, identity and/or location of each one or more fuel dispensers,
hours of business and/or products and/or amenities offered by each one or
more fuel dispensers, for each one or more fuel dispenser available fuel
types and/or fuel replacement cost, directions from the current vehicle
location to each one or more fuel dispensers, and a respective link to a
web page of each one or more fuel dispensers.

47. The system of claim 42, wherein the determined fuel strategy is based
in part on an applicable emission requirement.

48. The system of claim 42, wherein the determined fuel strategy
comprises one or more of the following: which of the first and second
fuels will be combusted by the engine; a fuel/air ratio to be combusted
by the engine; a mixture of the first and second fuels to be combusted by
the engine; an engine setting for the engine; an identity and/or location
of a fuel dispenser to be used by the operator; and a fuel specific
energy content to be employed.

49. The system of claim 42, wherein the processor is further operable to:
implement the determined fuel strategy, wherein implementing requires
changing a fuel type and/or mixture being provided to the engine.

50. A method, comprising: providing a vehicle, the vehicle carrying first
and second fuels, the first fuel being commonly available and the second
fuel not being as commonly available as the first fuel and wherein a fuel
injection system can provide selectively to a common engine at least one
of a selected one of the first and second fuels and a selected
combination of the first and second fuels without regard to the cetane
number or octane rating of the first and second fuels or a selected
combination of the first and second fuels.

[0002] The present invention relates generally to fueling optimization
strategies for vehicles capable of operating on several fuels. BACKGROUND

[0003] Multi-fuel vehicles are known. For example, cars with spark-ignited
engines (Otto cycle) have been outfitted with natural gas and propane
fuel capability so that they can run on gasoline, or they can switch and
run on either natural gas or propane. These engines can be switched on
the fly (that is when the engine is running and the vehicle is in
motion). There is, however, a limitation on this multi-fuel capability
since the fuels must have comparable ignition characteristics. The fuels
must have a high enough octane rating such that they are ignited as
prescribed by the spark ignition system not pre-ignited such as by
compression or hot surfaces before the prescribed spark ignition.

[0004] Some trucks are available with diesel engines (Diesel cycle) and
can run on diesel fuel or a mixture of diesel and natural gas. In the
latter case, the natural gas is the predominant fuel and diesel is
utilized as an ignition fuel. The fuels must have a high enough cetane
number such that they are ignited by compression at the prescribed time
of the combustion cycle.

[0005] Some fuels, such as gasoline and diesel, are widely available for
use in vehicles through a well-developed distribution infrastructure.
These fuels are well characterized in terms of ignition characteristics,
cost, energy content and emissions. Other fuels, such as natural gas,
bio-diesel, ethanol, methanol, butanol and hydrogen, are less readily
available for use in vehicles but may have cost and emissions advantages
over the widely available fuels.

[0006] For example, there is a distribution infrastructure for natural gas
although this infrastructure is less developed for vehicles than for
distribution to fixed commercial users. Both liquified natural gas
("LNG") and compressed natural gas ("CNG") forms of natural gas are
available to vehicles as fuels on a limited basis. Refueling a natural
gas-powered vehicle is often problematic since it requires special
equipment and special procedures, which are not always convenient for
vehicle operators.

[0007] There is currently a very limited infrastructure for hydrogen.
However, if hydrogen fuels were available, they would have excellent
emissions characteristics (no greenhouse carbon emissions at the point of
use). As with natural gas, refueling would require special equipment and
special procedures, which may not be convenient for vehicle operators.

[0008] The problem faced by developers of any new fuel is that they
require a widely available distribution infrastructure for a new fuel to
become accepted. However, the costs and risks of installing such an
infrastructure are too great unless acceptance of the new fuel can be
demonstrated. In addition, the introduction of a new fuel will cause
inconvenience to vehicle operators if the new fuel requires new
procedures, new equipment or is not readily available.

[0009] There therefore remains a need for innovative strategies for
introducing new fuels for vehicles that can operate on any of several
fuels where such introduction does not depend on a pre-existing
well-developed distribution infrastructure and where such introduction
can be made seamless to the vehicle operator.

SUMMARY

[0010] These and other needs are addressed by the various embodiments and
configurations of the present invention which are directed generally to a
multi-fuel strategy for vehicles utilizing gas turbine engines.

[0011] In an embodiment, ses a method and enabling apparatus are disclosed
for integrating a new fuel into an operating transportation system in a
continuous, seamless manner. This method is illustrated by diesel fuel
being gradually replaced by compressed natural gas ("CNG") in long haul
trucks. As can be appreciated, this same approach can be used for diesel
and LNG as well as other fuels as they are developed, characterized, mass
produced and eventually distributed. The method described herein
overcomes the risk associated with developing a new fuel when there is
little or no fuel distribution infrastructure in place.

[0012] Integrating a new fuel into an existing transportation situation
(for example, introducing CNG to a long haul truck fleet) can be
implemented using at least two enabling technologies. The first is an
engine system capable of operating seamlessly two or more fuels without
regard to the ignition characteristics of the fuels. The second is a
communications and computing system for implementing a fueling strategy
that both optimizes fuel consumption, guides the selection of fuel based
upon location, cost and emissions and allows the transition from one fuel
to another to appear substantially seamless to the truck driver.

[0013] A compact, high-performance gas turbine engine is a particularly
advantageous apparatus for the above strategy. The gas turbine engine can
have an advantage over reciprocating internal combustion engines, such
as, for example, diesel engines, in that it can typically burn a variety
of fuels without regard for ignition characteristics and with little or
no modification to the fuel injection system when switching from fuel to
fuel. This is so because the combustion process of a gas turbine engine
can be substantially continuous, requiring primarily a certain level of
specific energy from its fuels and not requiring special ignition
characteristics from its fuels. Therefore, gas turbine engines are
well-suited for multi-fuel operation.

[0014] The system of fueling strategy disclosed herein can allow the
operator of the vehicle, or the fleet manager to minimize operational
costs and/or fuel consumption by estimating the best combination of
fuels, fuel dispensing locations, and driving strategies. By carrying at
least one readily available fuel (such as diesel or gasoline), the
operator can be free of infrastructure shortcomings for other fuels that
may be less expensive or have desirable emission characteristics. With
the assistance of the system disclosed herein, the vehicle operator can
therefore efficiently manage the use of on-board fuels as well as
efficiently manage his driving schedule and route to continue to get a
better or best available fuel at a better or best available price.

[0015] In one configuration, a method is disclosed comprising:
determining, by a computer, a current spatial location of a vehicle, the
vehicle having at least differing first and second fuels for a common
engine of the vehicle;

[0016] determining, by the computer, at least one of fuel availability,
fuel pricing information and routing information for one or more fuel
dispensers within a determined range of the vehicle; and

[0017] based on the determined at least one of fuel availability, fuel
pricing information and routing information, determining, by the
computer, a fuel strategy involving at least one of the first and second
fuels.

[0018] In another configuration, a system is disclosed comprising: a
computer operable to:

[0019] determine a current spatial location of a vehicle, the vehicle
having at least differing first and second fuels for a common engine of
the vehicle;

[0020] determine at least one of fuel and pricing information for one or
more fuel dispensers within a determined range of the vehicle; and

[0021] based on the determined at least one of fuel and pricing
information, determine a fuel strategy involving at least one of the
first and second fuels.

[0022] In another configuration, a method and system are disclosed for:

[0023] determining, by a computer, a current spatial location of a vehicle
comprising a fuel;

[0024] determining, by the computer, a plurality of fuel dispensers within
a determined range of the current vehicle location; for each fuel
dispenser,

[0025] determining, by the computer, at least one of a price for the fuel,
a fuel consumption, and a cost to drive to the respective fuel dispenser
from the current vehicle location; and

[0026] presenting, by a computer and to the operator, at least one of the
fuel price, the fuel consumption, the driving cost, a recommendation of a
fuel dispenser of the plurality of fuel dispensers, and a ranking of at
least some of the plurality of fuel dispensers.

[0027] In another configuration, a vehicle is disclosed comprising:

[0028] a first fuel in a first fuel tank, the first fuel having an octane
rating ranging from about 60 to about 120;

[0029] a first fuel in a first fuel tank, the first fuel having a specific
energy, expressed as a low heat value, ranging from about 10 million
joules per kilogram to about 60 million joules per kilogram;

[0030] a second fuel in a second fuel tank, the second fuel having a
cetane number from about 10 to about 100;

[0031] a second fuel in a second fuel tank, the second fuel having a
specific energy, expressed as a low heat value, ranging from about 10
million joules per kilogram to about 60 million joules per kilogram; and

[0032] one of a turbine and microturbine engine; and a fuel injection
system operable to provide selectively to the engine the first fuel in
the substantial absence of the second fuel, the second fuel in the
substantial absence of the first fuel, and a mixture of the first and
second fuels.

[0033] In another configuration, a vehicle is disclosed comprising:

[0034] a first fuel in a first fuel tank;

[0035] a second fuel in a second fuel tank, the first and second fuels
having differing compositions;

[0036] one of a turbine and microturbine engine; and

[0037] a fuel injection system operable to provide selectively to the
engine the first fuel in the substantial absence of the second fuel, the
second fuel in the substantial absence of the first fuel, and a mixture
of the first and second fuels. At least one of the following is true:

[0038] (a) a volume of the second fuel tank to the volume of the first
fuel tank is in the range of from about 0.3:1 to about 1:1; and

[0039] (b) an available fuel energy of the first fuel in the first fuel
tank to the second fuel in the second fuel tank is in the range of from
about 2.5:1 to about 10:1.

[0040] In another configuration, a method and system are disclosed for:

[0041] providing a vehicle, the vehicle carrying first and second fuels,
the first fuel being commonly available and the second fuel not being as
commonly available as the first fuel and wherein a fuel injection system
can provide selectively to a common engine at least one of a selected one
of the first and second fuels and a selected combination of the first and
second fuels;

[0042] determining, by a processor-executable on-board satellite
positioning module, a current spatial location of the vehicle;

[0043] determining, by the processor, at least one of fuel and pricing
information for one or more fuel dispensers within a determined range of
the vehicle; and

[0044] based on the determined at least one of fuel and pricing
information, determining, by the processor, a fuel strategy involving at
least one of the first and second fuels.

[0045] In another configuration, a system is disclosed comprising a
processor operable to:

[0046] determine a current spatial location of the vehicle, the vehicle
comprising a commonly available first fuel and a less commonly available
second fuel,

[0047] a common engine,

[0048] a fuel injection system to provide selectively to the engine a
selected one of the first and second fuels; and

[0049] a processor operable to: [0050] determine at least one of fuel
and pricing information for one or more fuel dispensers within a
determined range of the vehicle; and [0051] based on the determined at
least one of fuel and pricing information, determine a fuel strategy
involving at least one of the first and second fuels.

[0052] In yet another configuration, a method is disclosed comprising:

[0053] providing a vehicle, the vehicle carrying first and second fuels,
the first fuel being commonly available and the second fuel not being as
commonly available as the first fuel and wherein a fuel injection system
can provide selectively to a common engine at least one of a selected one
of the first and second fuels and a selected combination of the first and
second fuels without regard to the cetane number or octane rating of the
first and second fuels or a selected combination of the first and second
fuels.

[0054] These and other advantages will be apparent from the disclosure of
the invention(s) contained herein.

[0055] The above-described embodiments and configurations are neither
complete nor exhaustive. As will be appreciated, other embodiments of the
invention are possible utilizing, alone or in combination, one or more of
the features set forth above or described in detail below.

[0056] The following definitions are used herein:

[0057] The terms "at least one", "one or more", and "and/or" are
open-ended expressions that are both conjunctive and disjunctive in
operation. For example, each of the expressions "at least one of A, B and
C", "at least one of A, B, or C", "one or more of A, B, and C", "one or
more of A, B, or C" and "A, B, and/or C" means A alone, B alone, C alone,
A and B together, A and C together, B and C together, or A, B and C
together.

[0058] The following definitions are used herein:

[0059] Automatic and variations thereof, as used herein, refers to any
process or operation done without material human input when the process
or operation is performed. However, a process or operation can be
automatic, even though performance of the process or operation uses
material or immaterial human input, if the input is received before
performance of the process or operation. Human input is deemed to be
material if such input influences how the process or operation will be
performed. Human input that consents to the performance of the process or
operation is not deemed to be "material".

[0060] The cetane number is a measure of the ignition quality of a fuel
and it is an indication of ease of self-ignition commonly in a Diesel
combustion cycle. The higher the cetane number, the more easily the fuel
is ignited under compression. It is a measure of a fuel's ignition delay;
the time period between the start of injection and start of combustion
(ignition) of the fuel. In a particular diesel engine, higher cetane
fuels will have shorter ignition delay periods than lower cetane fuels.
Cetane numbers are typically used for relatively light distillate diesel
fuels. The cetane number was originally a minimum of 45-49 in 1993, was
raised to 51 in 2000 to reduce ignition delay, improve combustion and
reduce exhaust emissions. The introduction of electronically controlled
injection allows a stepwise high-pressure injection of the fuel into the
combustion chamber. This makes direct fuel injection sufficiently smooth
and offers additional reductions of emissions so that the highly
efficient direct-injection diesel engines are suitable for passenger
cars, and they have since replaced the previously used swirl and
pre-chamber engines. However, low emissions and smooth engine running can
only be achieved with high-quality fuels and recent tests have shown that
synthetic diesel fuels with ultra-high cetane numbers can reduce
emissions further.

[0061] CNG means Compressed Natural Gas.

[0062] Computer-readable medium as used herein refers to any tangible
storage and/or transmission medium that participate in providing
instructions to a processor for execution. Such a medium may take many
forms, including but not limited to, non-volatile media, volatile media,
and transmission media. Non-volatile media includes, for example, NVRAM,
or magnetic or optical disks. Volatile media includes dynamic memory,
such as main memory. Common forms of computer-readable media include, for
example, a floppy disk, a flexible disk, hard disk, magnetic tape, or any
other magnetic medium, magneto-optical medium, a CD-ROM, any other
optical medium, punch cards, paper tape, any other physical medium with
patterns of holes, a RAM, a PROM, and EPROM, a FLASH-EPROM, a solid state
medium like a memory card, any other memory chip or cartridge, a carrier
wave as described hereinafter, or any other medium from which a computer
can read. A digital file attachment to e-mail or other self-contained
information archive or set of archives is considered a distribution
medium equivalent to a tangible storage medium. When the
computer-readable media is configured as a database, it is to be
understood that the database may be any type of database, such as
relational, hierarchical, object-oriented, and/or the like. Accordingly,
the invention is considered to include a tangible storage medium or
distribution medium and prior art-recognized equivalents and successor
media, in which the software implementations of the present invention are
stored.

[0063] Determine, calculate and compute and variations thereof, as used
herein, are used interchangeably and include any type of methodology,
process, mathematical operation or technique.

[0064] A DGE or Diesel Gallon Equivalent is a measure of the volume of a
fuel with an energy equivalent to the energy of 1 gallon of diesel fuel
on a low heat value basis.

[0065] A driving strategy as used herein refers to vehicles capable of
operating on two or more fuels and is a strategy for minimizing vehicle
operating costs by assimilating knowledge on fuel costs, fuel
consumption, fueling station locations, driving routes, driving terrain
and driving restrictions (if any) and driving times and using this
knowledge to pick a fueling location that minimizes overall vehicle
operating costs and/or fuel consumption, respecting cost of various
fuels, the driver's time and the types of routes to the various possible
fueling stations.

[0066] Energy density as used herein is energy per unit volume (joules per
cubic meter).

[0067] An energy storage system refers to any apparatus that acquires,
stores and distributes mechanical, chemical or electrical energy which is
produced from another energy source such as a prime energy source, a
regenerative braking system, a catenary or any external source of
electrical energy. Examples are a battery pack, a bank of capacitors, a
pumped storage facility, a compressed air storage system, an array of a
heat storage blocks, a bank of flywheels, a fuel reformer, an
electrolysis apparatus or a combination of storage systems.

[0068] An engine is a prime mover and refers to any device that uses
energy to develop mechanical power, such as motion in some other machine.
Examples are diesel engines, gas or steam turbine engines, microturbines,
Stirling engines, steam engines and spark ignition engines

[0069] A gas turbine engine as used herein may also be referred to as a
turbine engine or microturbine engine. A microturbine is commonly a sub
category under the class of prime movers called gas turbines and is
typically a gas turbine with an output power in the approximate range of
about a few kilowatts to about 700 kilowatts. A turbine or gas turbine
engine is commonly used to describe engines with output power in the
range above about 700 kilowatts. As can be appreciated, a gas turbine
engine can be a microturbine since the engines may be similar in
architecture but differing in output power level. The power level at
which a microturbine becomes a turbine engine is arbitrary and the
distinction has no meaning as used herein.

[0070] A GGE or Gasoline Gallon Equivalent is a measure of the volume of a
fuel with an energy equivalent to the energy of 1 gallon of gasoline fuel
on a low heat value basis.

[0071] An ignition characteristic of a fuel refers to a chemical or
physical property of the fuel that influences the condition under which
the timing and intensity of burning occurs. In reciprocating engines, the
timing of fuel ignition is typically desired in a narrow range of the
combustion cycle, typically as the peak compression point is approached.
Optimum ignition may be determined by performance or emissions
requirements or both. For fuels used in reciprocating engines, there are
many additives that may be used to modify ignition characteristics. In
diesel engines, the cetane number relates to the fuels ease of
self-ignition during compression. In a spark-ignition engines, the octane
rating is a measure of the resistance of the fuel to auto-ignition during
compression.

[0072] LHV means Low Heat Value and is the specific energy content
(sometimes called the heat of combustion) of a fuel obtained from
combusting the fuel wherein the water in the exhaust remains in the form
of vapor. The High Heat Value (HHV) is based on the water in the exhaust
being in liquid form. Since water vapor gives up heat energy when it
changes from vapor to liquid, the HHV value is larger than the LHV of the
fuel since it includes the latent heat of vaporization of water. The
difference between the high and low values is significant and can be as
much as about 10%.

[0073] LNG means Liquified Natural Gas. Natural gas becomes a liquid when
cooled to a temperature of about 175 K or lower. LNG is predominantly
methane, typically 90% or more methane, that has been converted
temporarily to liquid form for ease of storage or transport. LNG takes up
about 1/600th the volume of natural gas in the gaseous state. In a
typical LNG process, natural gas is transported to a processing plant
where it is purified. The gas is then cooled down in stages until it is
liquefied at close to atmospheric pressure (maximum transport pressure
set at around 25 kPa) by cooling it to approximately 175 K (-162 °
C.). The reduction in volume makes it much more cost efficient to
transport over long distances in specially designed cryogenic sea vessels
(LNG carriers) or cryogenic road tankers. The energy density of LNG is
60% of that of diesel fuel on a low heat value (LHV) basis. The density
of LNG is roughly 41 kg/cu m to 50 kg/cu m, depending on temperature,
pressure and composition. The heat value depends on the source of gas
that is used and the process that is used to liquefy the gas. The higher
heating value of LNG is estimated to be 24 MEL at -164 degrees Celsius.
This value corresponds to a lower heating value of 21 MJ/L.

[0074] Octane rating is a measure of the resistance of gasoline and other
fuels to auto-ignition in spark-ignition internal combustion engines. The
octane number of a fuel is measured in a test engine, and is defined by
comparison with the mixture of iso-octane and heptane which would have
the same anti-knocking capacity as the fuel under test: the percentage,
by volume, of iso-octane in that mixture is the octane number of the
fuel. For example, petrol with the same knocking characteristics as a
mixture of 90% iso-octane and 10% heptane would have an octane rating of
90. This does not mean that the petrol contains just iso-octane and
heptane in these proportions, but that it has the same detonation
resistance properties. Because some fuels are more knock-resistant than
iso-octane, the definition has been extended to allow for octane numbers
higher than 100. Octane rating does not relate to the energy content
(heating value) of the fuel. It is only a measure of the fuel's tendency
to burn in a controlled manner, rather than exploding in an uncontrolled
manner. Where octane is raised by blending in ethanol, energy content per
volume is reduced.

[0075] A permanent magnet motor is a synchronous rotating electric machine
where the stator is a multi-phase stator like that of an induction motor
and the rotor has surface-mounted permanent magnets. In this respect, the
permanent magnet synchronous motor is equivalent to an induction motor
where the air gap magnetic field is produced by a permanent magnet. The
use of a permanent magnet to generate a substantial air gap magnetic flux
makes it possible to design highly efficient motors. In the example of a
common 3-phase permanent magnet synchronous motor, a standard 3-phase
power stage is used. The power stage utilizes six power transistors with
independent switching. The power transistors are switched in ways to
allow the motor to generate power, to be free-wheeling or to act as a
generator by controlling frequency.

[0076] A prime power source refers to any device that uses energy to
develop mechanical or electrical power, such as motion in some other
machine. Examples are diesel engines, gas turbine engines, microturbines,
Stirling engines, spark ignition engines and fuel cells.

[0077] A power control apparatus refers to an electrical apparatus that
regulates, modulates or modifies AC or DC electrical power. Examples are
an inverter, a chopper circuit, a boost circuit, a buck circuit or a
buck/boost circuit.

[0078] Power density as used herein is power per unit volume (watts per
cubic meter).

[0079] A recuperator as used herein is a gas-to-gas heat exchanger
dedicated to returning exhaust heat energy from a process back into the
pre-combustion process to increase process efficiency. In a gas turbine
thermodynamic cycle, heat energy is transferred from the turbine
discharge to the combustor inlet gas stream, thereby reducing heating
required by fuel to achieve a requisite firing temperature.

[0080] A report producing device as used herein is any device or
collection of devices adapted to automatically and/or mechanically
produce a report. As one example, a report producing device may include a
general processing unit and memory (likely residing on a personal
computer, laptop, server, or the like) that is adapted to generate a
report in electronic format. The report producing device may also
comprise a printer that is capable of generating a paper report based on
an electronic version of a report.

[0081] Shorepower is a term used in the trucking business utilizing a
combination of truck-board and facility power systems. This is sometimes
referred to as shorepower since the hardware aboard the sleeper cab and
at the parking facility is similar to that found at boat marinas.

[0082] Specific energy as used herein is energy per unit mass (joules per
kilogram).

[0083] Specific power as used herein is power per unit mass (watts per
kilogram).

[0084] A switched reluctance motor is a type of synchronous electric motor
that induces non-permanent magnetic poles on the ferromagnetic rotor.
Torque is generated through the phenomenon of magnetic reluctance. A
switched reluctance motor may be known as a synchronous reluctance motor,
variable reluctance motor, reluctance motor or variable reluctance
stepping motor. Reluctance motors can have very high power density at
low-cost, making them ideal for many applications. Disadvantages are high
torque ripple when operated at low speed, and noise caused by torque
ripple. Until recently, their use has been limited by the complexity
inherent in both designing the motors and controlling them. These
challenges are being overcome by advances in the theory, by the use of
sophisticated computer design tools, and by the use of low-cost embedded
systems for motor control. These control systems are typically based on
microcontrollers using control algorithms and real-time computing to
tailor drive waveforms according to rotor position and current or voltage
feedback. The switched reluctance motor (SRM) is a form of stepper motor
that uses fewer poles than a synchronous reluctance motor. The SRM can
have the lowest construction cost of any industrial electric motor
because of its simple structure. Common usages for an SRM include
applications where the rotor must be held stationary for long periods and
in potentially explosive environments such as mining because it lacks a
mechanical commutator. The phase windings in a SRM are electrically
isolated from each other, resulting in higher fault tolerance compared to
inverter driven AC induction motors. The optimal drive waveform is not a
pure sinusoid, due to the non-linear torque relative to rotor
displacement, and the highly position dependent inductance of the stator
phase windings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0085]FIG. 1 is a line drawing of a gas turbine suitable for long haul
trucks. This is prior art.

[0086]FIG. 2 is a line drawing of a gas turbine installed in a long-haul
truck chassis and is compared to a diesel engine mounted in the same
vehicle frame. This is prior art.

[0087]FIG. 3 is a schematic of a truck with a second fuel tank on the
cab.

[0088]FIG. 4 is a schematic of a truck with a second fuel tank in the
trailer.

[0089] FIG. 5 is a schematic of a truck with fuel tanks in various
locations.

[0094] FIG. 10 shows typical variation of price as a function of station
size.

[0095]FIG. 11 shows breakeven cost for use of a lower price alternate
fuel.

[0096]FIG. 12 is a schematic representation of a network-based system for
optimizing fuel consumption and driving strategy for a multi-fuel
vehicle.

[0097]FIG. 13 is a flow chart illustrating an operational embodiment of
the system of FIG. 12.

DETAILED DESCRIPTION

[0098] Introduction of a New Fuel into an Operating Transportation System

[0099] The following is an example of how a new fuel can be integrated
into an operating transportation system in a continuous, seamless manner.
This example shows how diesel can be gradually be replaced by compressed
natural gas ("CNG") in long haul trucks. As can be appreciated, this same
approach can be used for other fuels as they are developed,
characterized, mass produced and eventually distributed. The approach
described herein overcomes the economic and investment risks associated
with developing a new fuel when there is little or no distribution
infrastructure in place for the new fuel.

Example of Replacing Diesel with CNG

[0100] Natural gas has been recognized as a practical replacement for
diesel fuel in terms of availability, cost and reduction of greenhouse
gas emissions. It appears that all other alternatives for transportation
fuels have as-yet unsolved social, economic and commercial consequences.
These consequences include their impact on world food prices,
uncompetitive costs, extensive land usage and often limited availability.
Natural gas can be used as a fuel either as compressed natural gas
("CNG") or liquified natural gas ("LNG").

[0101] As a replacement for diesel fuel in over-the-road Class 8 trucks,
LNG has been thought to be the most commercially viable form of natural
gas because of its relatively high energy density compared to CNG. Thus,
LNG is believed to be necessary to enable efficient transportation over
long distances. But in terms of costs, LNG as a fuel appears to be only
marginally lower in cost than diesel fuel. This impacts the commercial
risk of a trucking operator especially when an expensive truck is
dedicated to operate only on LNG. To mitigate this disincentive, various
levels of governments world-wide have instituted programs with economic
inducements (subsidies) to encourage the adoption natural gas as a truck
fuel.

[0102] The cost of LNG is generally higher than that of CNG because LNG
requires significantly more energy to liquify the natural gas to a
cryogenic fluid than to compress CNG to its most practical storage
pressure. Heretofore, natural gas has been much more abundant and
available at a lower cost outside of North America. Thus, in the past,
for natural gas to be practical as a widely used fuel, it would have to
come from overseas, typically in the form of LNG because of the large
distances over which it must be shipped. CNG however has become
attractive, especially for North America, because of the recent
application of horizontal drilling and hydraulic fracturing technologies
to open up vast new sources of natural gas (often referred to as shale
gas), which reduces the economic attractiveness of the more costly LNG
from overseas.

[0103] An objective of this invention is to enable the adoption of natural
gas as a transportation fuel for sound, sensible business reasons that
will not require the same level of subsidy, if it needs to be subsidized
at all. This method of introducing new fuels is expandable to other fuels
such as bio-diesel, for example, once the large-scale production problems
of such fuels are solved.

[0104] A primary reason that negatively impacts the business case for the
adoption of LNG as a replacement for diesel fuel, especially in long-haul
trucking, besides the obvious lack of fueling infrastructure, is the cost
of LNG and the limitations and consequences of owning and operating an
LNG truck. When comparing the commodity feedstocks of LNG (natural gas)
and diesel fuel (crude oil), the price comparison between the commodities
on an energy basis is generally quite different, with natural gas being,
on average, substantially below the cost of crude oil. However when
comparing the delivered finished products LNG and diesel fuel, the costs
are very comparable. This raises an important question for the
owner-operator of the advantages of converting solely to LNG. Do the
needs of special handling and servicing, and of higher cost of ownership
justify the transition to LNG from a more widely used fuel such as
diesel?

[0105] The reason for the significant difference between the commodity
cost of natural gas and the delivered cost of LNG is the capital cost of
all of the equipment, the regional liquefier plants, the on-highway
delivery tanker truck fleet, and the on-site LNG fuel storage and
dispensing, and additionally the high operating costs. The operating
costs are the energy costs for the energy-intensive liquefaction process,
the plant operating and maintenance costs, and the cost of operating the
LNG distribution system. The high costs incurred in setting up an LNG
production business are a barrier for smaller firms that could provide
competition and thereby help lower LNG costs. LNG is required by natural
gas-powered vehicles for range purposes. With the approach of the present
invention, this need no longer be a constraint.

[0106] The other form of natural gas used as a vehicle fuel is CNG. CNG is
significantly cheaper than LNG and has the potential to provide the
necessary, non-subsidized economic justification to use CNG as a
replacement for diesel fuel for over-the-road trucking The reason that
CNG has lower delivery cost is that in can be produced on-site, at a
truck stop, with the existing natural gas distribution system. That is,
CNG as a delivered fuel, requires substantially lower capital and
operating costs for its distribution infrastructure than LNG.

[0107] The primary argument against the use of CNG, especially for long
distance trucking, is that it limits the operating range of a truck
because CNG is a gaseous fuel with a relatively low energy density. Thus,
the argument is that CNG tanks take up too much space and/or not enough
fuel can be carried on-board. As the thinking goes, LNG is preferable for
extended range operations because of its higher energy density and
therefore the ability to get more fuel on board the truck's limited
space. Thus, LNG is often thought to be the most practical way to
introduce natural gas as a substitute for diesel fuel.

[0108] The present invention can offer a solution to the range limitation
of CNG so that the truck operator is not adversely affected or
inconvenienced. At the same time, the operator is able to reduce the
operating costs of the truck without the need for subsidies.

[0109] An enabling technology for the adoption of CNG as a replacement of
diesel fuel in over-the-road trucks is a practical gas turbine truck
engine that can use different types of fuels and change fuels on the fly
in a seamless fashion. Thus, fuel selection can become a discretionary
decision based on cost and/or fuel consumption as well as availability.
Therefore, if a truck that is powered with a gas turbine engine and has a
sufficiently large liquid fuel tank (for liquid fuels such as diesel or
gasoline for example) for an acceptable operating range, the CNG storage
capacity (operational range on CNG) is not critical to the truck's
economical operation. If the truck is not dependent on CNG for its
operation, then it may be operated beyond the range of CNG fueling
infrastructure and the sizing of the CNG storage can be determined based
on practical and economic considerations other than range.

[0110] A CNG fueled truck that does not totally depend on CNG, will be a
boon for the effort to adopt natural gas as a substitute for diesel fuel
on the interstates highway system because it gets around the conundrum of
(1) attracting customers for CNG before a CNG fueling infrastructure is
available and (2) financing a CNG fueling infrastructure before a
customer base is established.

[0111] As noted previously, an important aspect for the successful
implementation of CNG as a truck fuel is the rational sizing of the CNG
storage capacity based on with practical and economic considerations. CNG
storage on a truck is relatively bulky and expensive compared to standard
diesel fuel tanks on a diesel gallon equivalent (DGE) basis. CNG
cylinders that can store natural gas at about 3,600 psi occupy about 4
times the volume of a diesel fuel tank having the same operating range.
CNG cylinders that can store natural gas at about 4,200 psi occupy about
3.5 times the volume of a diesel fuel tank having the same operating
range. In addition, CNG tanks currently cost several times the cost of
diesel fuel tanks and can add significant weight as well as volume to the
fuel storage system.

[0112] What first becomes apparent is that the CNG fuel storage needs to
fit on the truck's tractor or trailer chassis while retaining the
standard, or at least, an acceptable amount of diesel fuel storage on
board. Secondly, a reasonable amount of CNG storage needs to be
considered because of cost and/or fuel consumption. Carrying any more CNG
that is needed for the minimum amount of acceptable convenience,
adversely affects the operating economics of the truck. Having too little
CNG storage on board is also counterproductive as the driver will need to
refill the CNG tanks more often than usual, resulting in the driver
wasting time that will adversely affect schedule.

[0113] Sizing the CNG fuel tanks so that under normal driving conditions,
refilling would coincide with the driver's need for breaks appears to be
practical. Thus, if the driver goes about 4 hours between breaks (meals)
and covers about 250 miles during that period and is getting about 6.5
miles per gallon, the operator will need at least 38 DGE of CNG on board
to cover that distance with natural gas (250 miles/6.5 miles per
gallon=38.5 gallons). Returning to the physical layout of the truck
tractor or trailer, space for about 40 to 50 DGE of CNG storage appears
to be available without compromising the operation and safety of the
vehicle.

[0114] By way of illustration, for the above case of an approximately 4
hour driving range on CNG, the volumetric ratio of CNG storage compared
to liquid fuel storage volume is typically in the range of from about
0.3:1 to about 1:1, and even more typically in the range of from about
0.4:1 to about 0.8:1. Stated another way, the available fuel energy ratio
of stored liquid fuel to stored CNG is typically in the range of from
about 2.5:1 to about 10:1, and even more typically in the range of from
about 4:1 to about 8:1.

[0115] By way of further illustration, for the above case of approximately
equal driving ranges, the volumetric ratio of CNG storage compared to
liquid fuel storage volume is typically in the range of from about 1:1 to
about 6:1, and even more typically in the range of from about 3:1 to
about 5:1.

Example of Refueling Procedure to Accommodate New Fuel

[0116] Refueling a truck more than 1 or 2 times per day could take an hour
out of the driver's day. This could be considered an inconvenience
especially if the driver is used to an operating range that the typical
300 gallon diesel fuel tank yields between refueling. The present
invention proposes a method for substantially minimizing this
time-consuming inconvenience of periodic re-fillings of a limited
capacity CNG fuel tank.

[0117] When the driver takes a break from driving, the driver often stops
at a large truck stop. Here the driver can park his truck in a designated
spot. If this spot is equipped with a CNG dispenser or a CNG filling
post, the driver can connect his truck to a source of CNG in seconds, go
about business, return, disconnect his re-fueled truck from the CNG
dispenser, again in seconds, and drive off. This entire procedure would
be virtually the same as his normal routine and he will have refueled the
truck with CNG in the process. As can be appreciated, the recording and
purchasing of the CNG can all be handled electronically.

[0118] The gas turbine engine can have an advantage over other types of
internal combustion engines, such as for example diesel engines, in that
they can typically burn a variety of fuels without regard for ignition
characteristics and with little or no modification to the fuel injection
system. Gas turbines are substantially insensitive to the ignition
characteristics of fuels and can operate on fuels having a wide range of
specific energy values. This is principally because the combustion
process in a gas turbine engine is substantially continuous. The
combustion process in a reciprocating engine is cyclical and requires
ignition of new fuel introduced during each cycle. Therefore, gas turbine
engines are well-suited for multi-fuel operation. For example, a vehicle
utilizing a gas turbine engine may be operated on either diesel fuel
which is widely available for vehicles, or on CNG or LNG (the latter two
being less widely available for vehicles) simply by selecting the fuel
delivery system. For example, gas turbines can be fitted with injectors
that permit both gaseous and liquid fuels to be used. The vehicle can be
outfitted with a diesel fuel tank and a CNG or LNG fuel tank.

[0119] In one vehicle design, the vehicle has multiple on-board stored
fuel receptacles, each receptacle including a different type of gaseous
or liquid fuel. For example, a first fuel can be diesel fuel, and a
second fuel can be CNG. In a further example, the first fuel can be a
renewable or a nonrenewable fuel while the second fuel can also be a
renewable or a nonrenewable fuel. The vehicle has a prime mover, such as
a gas turbine engine, that is substantially independent of one or more of
the fuel additives required by reciprocating engines. By way of
illustration, such additives may include for example, anti-oxidants,
metal de-activators, and anti-stall agents, and other antiknock chemicals
for gasolines and cold-flow improvers, wax anti-settling additives,
detergents, anti-corrosion, anti-wear additives and anti-foam additives
for diesel fuels.

[0120] An innovative feature of this system is that the change from one
fuel to another can be made on the fly, even if one fuel is a liquid
(diesel in this example) and one is gaseous (CNG in this example). Unlike
other dual fuel (diesel/natural gas) truck engine technology, a gas
turbine engine can replace commonly at least about 75%, more commonly at
least about 80%, more commonly at least about 85%, more commonly at least
about 90%, more commonly at least about 95%, and even more commonly about
100% of the diesel fuel with natural gas. This is so because the piston
dual fuel engine needs to retain a portion of its diesel fuel for a pilot
ignition source for the natural gas.

[0121] If, for example, natural gas is the more desirable fuel from either
or all of a cost standpoint, a fuel consumption standpoint or an
emissions standpoint, then it would be preferable to operate the vehicle
on natural gas as long as natural gas were readily available. If the
vehicle could not be readily refueled with natural gas, it could be
switched to operate on diesel, which is less desirable but almost
universally available. It is also noted that a gas turbine engine can be
configured to operate on a mixture of liquid and gaseous fuels and/or
even on a mixture of liquid fuels such as, for example, a mixture of
gasoline and diesel. With the present invention it may also be possible
to achieve a net reduction of emissions by selecting a ratio of natural
gas to diesel, allowing the engine to be operated in a minimum emissions
mode. The accelerated flame of the diesel fuel in a diesel/natural gas
mix may have beneficial effects in the design of the gas turbine
combustor.

[0122] Another aspect of the present invention is that refueling episodes
for the less widely available fuels may be designed to resemble the
refueling episodes for the more widely available fuels so that vehicle
operators will choose a fuel based on cost, fuel consumption or emissions
criteria or any combination of the three, and not on the convenience of
the fuel dispensing system to which they are accustomed.

[0123] As an example of this, a vehicle can be parked and slow-filled with
CNG while the operator uses the store/restaurant facility. In slow-fill,
the CNG is pressurized from a lower pressure to the maximum pressure of
the vehicle's CNG gas storage cylinders (typically about 3,600 psia or
about 25 kPa). This method of filling uses a minimum of energy for gas
compression and permits more fuel to be stored due to the more accurate
reading of tank pressure and temperature during the fill, thus optimizing
tank fill by measuring pressure and temperature and using this
information to modulate the flow. This is in contrast to rapid filling
(which is more convenient and mimics filling with diesel or gasoline,
where the operator does the filling and then moves on) wherein the CNG is
expanded from a higher pressure source down to the maximum pressure of
the vehicle's CNG storage cylinders. This method of filling uses more
energy for compression to the higher pressure storage tanks, typically
about 20% to about 25% more energy, and this is reflected as an increased
fuel price (typically about 10 to about 12 cents of every dollar).

[0124] The above discussion of integrating a new fuel into an existing
transportation situation (such as the above example of introducing CNG to
a long haul truck fleet) can be implemented with at least two enabling
technologies. The first is an engine capable of operating seamlessly on
multiple fuels. The second is a system of determining a fueling strategy
that reduces overall operational costs (including fuel consumption) and
makes the transition from one fuel to another seamless to the truck
driver.

Electrification Stations

[0125] Truck engine idling is increasingly recognized as an aesthetic and
environmental problem across the United States. Truck Stop
Electrification (TSE) is an approach currently being deployed to reduce
heavy truck idling at truck stops and rest areas. Drivers of the nearly
500,000 long-haul trucks in the United States must rest for specific
periods as prescribed by U.S. Department of Transportation regulations.
Long-haul truck drivers typically idle their engines to heat or cool
sleeper cab compartments, and to maintain vehicle battery charge while
electrical appliances such as televisions and microwaves are in use. In
colder climates, idling also keeps engine oil and fuel warm enough to
prevent engine starting and operating problems. The average sleeper cab
tractor idles for 1,830 hours annually, and consumes approximately one
gallon of diesel fuel per hour. However, idling increases fuel and
maintenance costs, emissions, and noise.

[0126] Options to reduce idling include auxiliary power units and
fuel-fired heaters. Both have significant operational, environmental or
cost disadvantages compared to TSE. TSE is a preferred approach to
anti-idling because of zero on-site air emissions and minimal noise
emissions. Heavy truck engine idling can be virtually eliminated at
TSE-equipped locations and thus can improve environmental conditions at
truck parking areas and in the communities that surround them.

[0127] The combination use of truck-board and facility power systems is
also frequently referred to as shorepower, since the hardware aboard the
sleeper cab and at the parking facility is similar to that found at boat
marinas. The shorepower system gives access to 120- or 240-Volt
electrical power from a land-based electrical power source. This approach
separates the electrical supply available at a parking facility from the
accessory system installed in a tractor.

[0128] An electrified fueling station is prior art. A typical stationary
shorepower infrastructure consists of 20 or more RV-style power
pedestals. The pedestals may be equipped with AC electrical power, cable
TV, Internet, and telephone service connections. Typically, one pedestal
will be provided for each of the 20 or more parking spaces. A payment
system or payment kiosk can be placed in each TSE parking space or can be
placed centrally to the about 20 or more shorepower parking berths.

[0130] Liquid Natural Gas (LNG) fueling stations are prior art. LNG
fueling stations are currently used for fueling heavy and medium duty
vehicles. The LNG fuel is produced at LNG plants from pipeline gas cooled
to about -260F (about 110 K) and delivered in LNG trailers to fuel
stations. These plants can produce typically about 160,000 to about
300,000 gallon per day and typically can store about 1.5 to about 2
million gallons of LNG on site.

[0131] There are currently two Grades of LNG. The first is Blue (Cold) LNG
for Westport GX engines and the second is Green (Warm) LNG for
spark-ignited engines. Blue LNG increases storage capacity and range and
is optimized for Westport GX engines. Its advantages are increased truck
range, increased fuel economy and elimination of venting losses. It is a
colder fuel, stored in on-board tanks at about -225 F and about 35 psig.
Green LNG is optimized for CWI ISL-G spark-ignited engines. It is stored
in on-board tanks at about -195 to about -207 F and about 85 to about 120
psig.

[0132] LNG fueling pumps are prior art. These fueling pumps can dispense
fuel at rates comparable to diesel or gasoline pumps. Fueling may be
carried out by the vehicle operator. A typical LNG truck stop will
accommodate about 25 to about 50 trucks per hour with about 10 dispensing
lanes and with about 100,000 gallons of fuel storage on site.

Compressed Natural Gas (CNG) Stations

[0133] Compressed Natural Gas (CNG) fueling stations are prior art. CNG
fueling stations are currently used for fueling light, medium, and
medium-heavy duty vehicles. Natural gas is delivered by pipeline to
fueling station via the same distribution network used for gas that heats
homes and is used for cooking The natural gas is compressed at the
station to about 3,600 psi for dispensing and may be dispensed in a
manner similar to gasoline or diesel. When dispensed in this manner, it
is known as fast fueling. It is typically stored on the vehicle in one or
more gas cylinders.

[0134] CNG stations typically dispense about 35 million DGEs of CNG
annually, growing at about 10% per year. Compressed natural gas is the
same fuel that is used in many homes and is delivered in a pipeline by
the local utility. CNG is used at about 3,600 psi as a gaseous fuel and
is thus different from LNG, which is cryogenic. It is sold in therms,
Gasoline Gallon Equivalents (GGEs) or Diesel Gallon Equivalents (DGEs).
On-board storage capacity is enough to provide sufficient range for
regional trucking CNG meets clean truck program requirements, it is
typically a low fuel price requiring on-site fuel storage. CNG is
odorized for safety and there is no waste due to boil off.

[0135] There may be public and private fueling stations. A small private
station may serve about a 50 truck fleet and dispense about 60,000 DGEs
per month. A large private station may serve about a 200 truck fleet and
dispense about 250,000 DGEs per month.

[0136] Typical commercial CNG dispensers are operated like a gasoline or
diesel filling pump apparatus. This dispensing unit may be operated as a
fast fueling pump where the vehicle operator may do the dispensing or it
may be operated as a slow fueling pump where the vehicle operator can
leave the vehicle to use a nearby rest stop, restaurant and store. As
will be discussed below, the slow fueling method for CNG has a
significant energy advantage over the fast fueling method for CNG and
therefore the slow fueling method has a significant cost advantage as
well. A typical commercial filling point that would be operated as a slow
fueling pump where the vehicle operator can leave the vehicle parked for
a substantial period (many minutes to a couple of hours).

[0137] One advantage of CNG as a fuel is that there already exists a
natural gas distribution system in most countries. For example, a natural
gas distribution network comprised of main natural gas distribution trunk
lines and the smaller distribution pipelines exists in the United States
and this network extends into Canada and Mexico. Currently, an LNG fuel
station costs approximately 4 times more to install than a CNG fuel
station.

Exemplary Gas Turbine Engine

[0138] A gas turbine engine is an enabling engine for efficient multi-fuel
use and, in particular, this engine can be configured to switch between
fuels while the engine is running and the vehicle is in motion (on the
fly). In addition, a gas turbine engine can be configured to switch on
the fly between liquid and gaseous fuels or operate on combinations of
these fuels. This is possible because combustion in a gas turbine engine
is continuous (as opposed to episodic such as in a reciprocating piston
engine) and the important fuel parameter is the specific energy content
of the fuel (that is, energy per unit mass) not its cetane number or
octane rating. The cetane number (typically for diesel fuels) or octane
rating (typically for gasoline fuels) are important metrics in piston
engines for specifying fuel ignition properties.

[0139] The gas turbine engine such as shown in FIG. 1 enables the fuel
strategy of the present invention. This engine is prior art although
efficient multi-fuel configurations will require innovative
modifications. This is an example of a 375 kW engine that uses
intercooling and recuperation to achieve high operating efficiencies (40%
or more) over a substantial range of vehicle operating speeds. This
compact engine is suitable for light to heavy trucks. Variations of this
engine design are suitable for smaller vehicles as well as applications
such as, for example, marine, rail, agricultural and power-generating.
One of the principal features of this engine is its fuel flexibility and
fuel tolerance. This engine can operate on any number of liquid fuels
(gasoline, diesel, ethanol, methanol, butanol, alcohol, bio diesel and
the like) and on any number of gaseous fuels (compressed or liquid
natural gas, propane, hydrogen and the like). This engine may also be
operated on a combination of fuels such as mixtures of gasoline and
diesel or mixtures of diesel and natural gas. Switching between these
fuels is generally a matter of switching fuel injection systems and/or
fuel mixtures.

[0140] For example, at a first time a gas turbine engine burns a first
fuel mixture, and at a second time a different second fuel mixture. The
first and second mixtures include at least one uncommon fuel type. The
first mixture, for instance, can have diesel as the primary fuel, and the
second mixture CNG or LNG as the primary fuel. In another illustration,
the first mixture, by way of further illustration, is a first mixture
ratio of fuels A and B, and the second mixture a different second mixture
ratio of fuels A and B. In all of the above illustrations, the specific
energy of the first fuel mixture is commonly at least about 20%, more
commonly at least about 50%, and even more commonly at least about 80% of
the specific energy of the second fuel mixture. For example, a
reciprocating engine typically burns fuels having a low heat value (LHV)
in the range of about 40 million to about 55 million Joules per kilogram.
A gas turbine engine can burn fuels having a low heat value (LHV) in the
range of about 10 million to about 55 million Joules per kilogram.

[0141] Not only can a gas turbine burn fuels of lower specific energy, but
they can burn less complex fuels as discussed below. This has the
potential of reducing the costs of refining fuels by simplifying fuel
requirements.

[0142] This engine operates on the Brayton cycle and, because combustion
is continuous, the peak operating temperatures are substantially lower
than comparable sized piston engines operating on either an Otto cycle or
Diesel cycle. This lower peak operating temperature results in
substantially less NOx emissions generated by the gas turbine engine
shown in FIG. 1. This figure shows a load device 109, such as for example
a high speed alternator, attached via a reducing gearbox 117 to the
output shaft of a free power turbine 108. A cylindrical duct 184 delivers
the exhaust from free power turbine 108 to a plenum 114 which channels
exhaust through the hot side of recuperator 104. Low pressure compressor
101 receives its inlet air via a duct (not shown) and sends compressed
inlet flow to an intercooler (also not shown). The flow from the
intercooler is sent to high pressure compressor 103 which is partially
visible underneath free power turbine 108. As described previously, the
compressed flow from high pressure compressor 103 is sent to the cold
side of recuperator 104 and then to a combustor which is contained inside
recuperator 104. The flow from combustor 115 (whose outlet end is just
visible) is delivered to high pressure turbine 106 via cylindrical duct
156. The flow from high pressure turbine 106 is directed through low
pressure turbine 107. The expanded flow from low pressure turbine 107 is
then delivered to free power turbine 108 via a cylindrical elbow 178.

[0143] This engine has a relatively flat efficiency curve over wide
operating range. It also has a multi-fuel capability with the ability to
change fuels on the fly as described in U.S. Provisional Application No.
61/325578 entitled "Multi-Fuel Vehicle Strategy", filed on Apr. 19, 2010
and which is incorporated herein by reference.

[0144] For example, in a large Class 8 truck application, the ability to
close couple turbomachinery components can lead to the following
benefits. Parts of the engine can be modular so components can be
positioned throughout vehicle. The low aspect ratio and low frontal area
of components such as the spools, intercooler and recuperator facilitates
aerodynamic styling. The turbocharger-like components have the advantage
of being familiar to mechanics who do maintenance. It can also be
appreciated that the modularity of the components leads to easier
maintenance by increased access and module replacement. Strategies for
replacement based on simple measurements filtered by algorithms can be
used to optimize maintenance strategies. These strategies could be driven
by cost, fuel consumption, emissions or efficiency. In a Class 8 truck
chassis, the components can all be fitted between the main structural
rails of the chassis so that the gas turbine engine occupies less space
than a diesel engine of comparable power rating. This reduced size and
installation flexibility facilitate retrofit and maintenance. This
ability also permits the inclusion of an integrated APU on either or both
of the low and high pressure spools such as described in U.S. Provisional
Application No. 61/361,083, entitled "Improved Multi-Spool Intercooled
Recuperated Gas Turbine", filed Jul. 2, 2010 which is incorporated herein
by reference. This ability also enables use of direct drive or hybrid
drive transmission options.

[0145]FIG. 2 is a line drawing of a gas turbine engine 201 along with the
outline of a comparable power diesel engine 211 in a Class 8 truck cab
210. This is prior art. This figure shows a high-performance ˜375
kW gas turbine engine 201 mounted in a Class 8 truck chassis and, for
comparison, a ˜375 kW diesel engine 211 (without transmission and
emissions control equipment). An intercooler 203 which is associated with
gas turbine engine 201 is also shown. Duct 202 is also item 184 of FIG.
1. The gas turbine engine is substantially smaller than the diesel engine
and can be readily operated on a variety of fuels that the diesel engine
cannot utilize. Diesel fuel tank 212 is also shown.

[0146] The gas turbine engine described in FIGS. 1 and 2 can be configured
with either a conventional metallic combustor or a so-called thermal
reactor. The thermal reactor offers a practical means of achieving the
necessary thermodynamic conditions for a gas turbine thermal reactor
which allow the unpressurized gaseous fuel and air to be introduced at
the engine air inlet. This strategy of fuel introduction and mixing
eliminates the typical gaseous fuel pressurization system and associated
parasitic losses, cost and complexity. The thermal reactor is typically
designed for use in a multistage intercooled compressor, a recuperator
and a multistage turbine to achieve the requisite thermodynamic
conditions for consistent combustion. The thermal reactor can be used
with liquid fuels where, preferably, the fuel is introduced between the
recuperator and the combustor. In the case of liquid fuels, much less
energy and a smaller apparatus are normally required to pressurize the
liquid fuel with its much lower compressibility for injection into the
compressed air stream. Reduction in Fuel Complexity As noted previously,
a gas turbine engine is a continuous combustion engine and does not
require blending, additives or special techniques for ignition.
Reciprocating engines require ignition in each cylinder thousands of
times per second and therefore require additives and special techniques
for ignition to achieve proper performance and control of emissions.
Further, for reciprocating engines to achieve thermal efficiencies as
high as the most advanced gas turbines engines, the peak combustion
temperatures must be considerably higher than the relatively constant
temperature in a continuous combustion gas turbine engine. Since
comparable power reciprocating and gas turbine engines combust the same
amount of fuel energy per unit time, the gas turbine engine will always
operate at a substantially lower temperature than the peak temperature
generated by combustion every cycle by a reciprocating engine. This means
that reciprocating engines will produce higher levels of NOx than a gas
turbine engine of comparable power since NOx production increases
approximately exponentially with temperature. To meet current emissions
requirements, reciprocating engines must continually improve the quality
of combustion through improvements in one or more of cylinder design,
fuel blending, fuel additives and fuel injection techniques.

[0147] Consider the complexity of gasolines and diesel fuels for example.
Gasolines are complex mixtures of hydrocarbons. Various grades of
gasolines are blended to promote high anti-knock quality, ease of
starting, quick warm-up, low tendency to vapor-lock, and low engine
deposits. The components used in blending gasoline can be used to produce
light straight-run gasoline or isomerate, catalytic reformate,
catalytically cracked gasoline, hydrocracked gasoline, polymer gasoline,
alkylate, n-butane, and such additives as ETBE, TAME (tertiary amyl
methyl ether), and ethanol may be used. Other additives, for example,
antioxidants, metal de-activators, and anti-stall agents are included
with the antiknock chemicals added. The quantity of antiknock agents
added must be determined by making octane blending calculations.

[0148] Today, diesel fuel is now a complex blend of hydrocarbons with an
even wider range of additives than gasoline. Important performance
aspects brought about by additives such as lubricity additives have been
included. Further compositional changes are required to ensure low
exhaust emissions. The continued improvement of the diesel engine to an
even more efficient and environmentally acceptable prime mover with
complex mixture preparation systems, such as high-pressure common-rail
injection, requires high-quality diesel fuels. New refinery technologies,
synthetic fuels or components, new additives and to some extent fuel from
biomass will help to further improve performance. To reduce carbon
dioxide emissions, low concentrations of fatty acid methyl esters
produced from biomass as diesel fuel components can be added. With the
reduction in sulfur, anti-wear additives have been developed and added to
protect fuel pumps and nozzles. The cetane number was raised to 51 in
2000 to reduce ignition delay, improve combustion and reduce exhaust
emissions. Being liquids, cetane improvers such as ethyl hexyl nitrates
(EHN) are used to improve ignition performance. An important group of
additives are cold-flow improvers and wax anti-settling additives.
Another type of additive is detergents, which keep injector nozzles clean
and help to keep exhaust emissions from increasing over time.
Anti-corrosion and anti-wear additives (so called lubricity additives)
protect not only the engine but also the fuel distribution system.
Anti-foam additives remain important as they reduce foaming when vehicle
tanks are refilled at service stations, preventing spillage and overfill.

[0149] The need for blending and many of these fuel additives in both
gasoline and diesel fuels can be reduced or eliminated for use in gas
turbine engines since gas turbine engines can combust most fuels without
special ignition additives and never achieve the high transient
combustion temperatures where most NOX is produced. It is also noted
that, aromatics such as benzene, toluene and xylene used as octane
enhancers for gasoline, are known to be carcinogenic. These could be
reduced or eliminated from fuels for use in a gas turbine engine.

Multi-Fuel Truck Configurations

[0150] The multi-fuel configurations discussed below have the advantage of
extending the range of operation of the vehicle and provide an
opportunity for optimizing vehicle economics by providing a convenient
choice of using lower cost fuels when these are available or operating on
readily available fuels when the preferred fuel is not readily available.
Remote monitoring of the vehicle can be utilized to optimize vehicle
economics by dispatch from a central logistics office.

[0151]FIG. 3 is a schematic of a gas-turbine powered truck with a second
fuel tank mounted behind the tractor cab. This figure shows a tractor 301
pulling a trailer 302. As an example, the tractor 301 is shown with
diesel fuel tanks 303 mounted under the tractor cab. The diesel tanks can
have a capacity in the range of about 150 to about 400 gallons of diesel
fuel, with about 300 gallons of diesel fuel being typical. CNG tanks 304
are shown mounted behind the tractor cab. CNG tanks 304 are available
commercially with capacity in the practical range of about 25 to about
150 DGEs with about 40 DGEs being required for about 250 miles of driving
range.

[0152]FIG. 4 is a schematic of a gas-turbine powered truck with a second
fuel tank mounted inside the trailer. This figure shows a tractor 401
pulling a trailer 402. As an example, the tractor 401 is shown with
diesel fuel tanks 403 mounted under the tractor cab. These tanks
typically have a capacity similar to that set forth above, with about 300
gallons of diesel fuel being typical. CNG tanks 404 are shown mounted
inside the trailer 402. CNG tanks 404 are available commercially with
capacity in the practical range of about 25 to about 150 DGEs with about
40 DGEs being required for about 250 miles of driving range.

[0153]FIG. 5a is a schematic of a gas-turbine powered truck with a second
fuel tank under the trailer. This figure shows a tractor 501 pulling a
trailer 502. As an example, the tractor 501 is shown with diesel fuel
tanks 503 mounted under the tractor cab. These tanks typically have a
capacity similar to that set forth above, with about 300 gallons of
diesel fuel being typical. CNG tanks 504 are shown mounted under the
trailer 502. CNG tanks 504 are available commercially with capacity in
the practical range of about 25 to about 150 DGEs with about 40 DGEs
being required for about 250 miles of driving range.

[0154]FIG. 5b is a schematic of a gas-turbine powered truck showing fuel
tanks 513 and 514 mounted under the tractor cab 512. Fuel tank 513 may
contain a first fuel and fuel tank 514 may contain a second fuel. For
example, fuel tank 513 may contain 100 to 200 gallons of liquid fuels
such as diesel or gasoline or a mixture of both. Fuel tank 514 may
contain 100 to 200 gallons of LNG or alternately fuel tank 514 may
contain 25 to 50 DGE of CNG.

[0155] As can be appreciated, the above fuel tank configurations can
include any combination of liquid and/or gaseous fuel tanks containing
any combination of fuels that can be combusted in a gas turbine engine.

[0156]FIG. 6 is a schematic of a gas-turbine powered truck with several
fuel tanks

[0157] This figure shows a tractor 601 pulling a trailer 602. As an
example, the tractor 601 is shown with diesel fuel tanks 603 mounted
under the tractor cab. These tanks typically have a capacity similar to
that set forth above, with about 300 gallons of diesel fuel being
typical. CNG tanks 604 are shown mounted behind the tractor cab. CNG
tanks 604 are available commercially with capacity in the practical range
of about 25 to about 150 DGEs with about 40 DGEs being required for about
250 miles of driving range. Hydrogen tanks 605 are shown mounted inside
the trailer 602. Hydrogen tanks 605 are available commercially with
capacity commonly in the range of about 10 to about 50 DGEs. Methanol
tanks 606 are currently available commercially with capacity in the range
of about 100 to about 500 DGEs.

[0158] In this example, the truck engine is a gas turbine engine that can
burn any of diesel, natural gas, methanol or hydrogen fuels. When natural
gas, methanol or hydrogen fuels are not available, the truck can be
operated on diesel. If natural gas is available and is cheaper than
diesel, then the truck would preferably be operated on natural gas. The
truck can be operated on methanol if this fuel is available. The truck
can include a reformer which can convert methanol into hydrogen and
carbon dioxide, with the hydrogen being stored in tanks 605. The carbon
dioxide can be stored in tanks (not shown) for disposal at a carbon
dioxide disposal site. The truck can then be operated on hydrogen in
areas where other fuels are restricted or prohibited because of
greenhouse gas emission considerations.

Multi-Fuel Fueling Station

[0159] FIG. 7 is a schematic of an example multi-fuel fueling station.
This figure shows a typical fueling station accessed from a main
thoroughfare 701, such as for example an interstate highway or a
connector to an interstate highway. The fueling station is comprised of a
parts store/restaurant 702, a convenience store 707, several auto parking
areas 709, several truck diesel pump dispensing lanes 703, several auto
gasoline and diesel pump dispensing lanes 705, a truck parking area 706,
an overnight truck electrification (TSE) truck parking area 708 and a
truck parking area with several CNG fuel fill posts 704. Additionally
there can be separate CNG and LNG dispensing lanes similar to the truck
diesel pump dispensing lanes 703, dispensing natural gas. As can be
further appreciated, there can be other fuel pump dispensing other liquid
fuel like methanol, bio-diesel, and ethanol but unlike CNG would require
supervised filling on a catchment surface of a fueling lane and not in a
unpaved parking area.

[0160] In this example, a gas turbine powered truck with multi-fuel
capability such as shown in FIGS. 3 through 6 can be refueled with either
or both diesel and CNG. Diesel fuel can be pumped by the vehicle operator
or a station attendant in the normal manner. In the case of CNG, CNG can
be pumped by the vehicle operator or a station attendant using a high
speed fueling system or the vehicle can be refueled by the vehicle
operator who, after initiating refueling, goes to the store/restaurant
while CNG tank is being refueled by a slower fueling system. The design
of the dual fuel or multi-fuel fueling station is such that the vehicle
operators perform fueling operations in the manner to which they are
accustomed.

[0161] For CNG or other gaseous fuels, a slow fueling system can be
practical. With this method, the vehicle remains in a parking space which
is equipped with a CNG or another gaseous fuel dispensing system. The
parking space may also include a TSE capability. The vehicle operator
would initiate fueling and then leave the vehicle while he/she uses the
restaurant/store facilities. The slow fueling system is preferred because
it uses less energy and therefore would result in a fuel cost savings.
With this method, the gaseous fuel is compressed from a low pressure line
or storage tank to the final pressure in the vehicles fuel tank
(typically in the range of about 3,600 psi to about 4,500 psi). The slow
fueling method also allows the heat generated by compression to dissipate
through the fuel tank walls.

[0162] The refueling facility can transmit fuel availability, price,
facility availability. Upon selection of a fueling strategy by the driver
and/or the computer, an ID tag and fuel station pump location can be
transmitted to the on board computer that optimizes driver experience and
minimizes wait times. The facility can update fuel port allocations in
real time to reduce any delays. The vehicle ID number can be associated
with the transaction number for fuel pump activation and the ensuing
financial transaction. The fuel pump can only permit fueling when the
vehicle ID and transaction number match for a specific delivery port at
the refueling station. For heavy use periods premium lanes with no wait
may be available for an increased fuel cost.

[0163] The refueling transaction can be either on a credit basis, taken
from a prepaid account, or accumulated for separate invoicing but be
substantially automated without additional driver input. Payment for
fueling can be accomplished by several means, including but not limited
to cash, credit card, debit card, automated license scanning and
subsequent e-mailed or mailed billing and the like. If an emissions or
greenhouse credit is available, this credit can also be accounted by any
number of well-known means.

[0164] The energy to compress a kilogram of natural gas to about 3,600 psi
with a slow fueling system is approximately 1.3 MJ. The energy to
compress a kilogram of natural gas to about 3,600 psi with a fast fueling
system is about 1.6 MJ or about 23% more energy than with a slow fueling
system .

[0165]FIG. 8 is a schematic of a CNG fuel dispensing system such as may
be included in the truck stop of FIG. 7. This figure shows several fuel
filling posts 801 at which large trucks can re-fuel their CNG tanks
Fueling a 20 to 50 DGE CNG tank is expected to take from about 15 to
about 30 minutes, depending on how much fuel is required by each truck
and how many trucks are being fueled at the same time. CNG is typically
stored in three CNG storage tanks 805 in a cascaded storage arrangement.
CNG is dispensed to multiple filling posts 810 using a single flow meter
804. Valves 803 control metered amounts of CNG to the various filling
posts. Valves 807 control which storage tank 805 provides the CNG. The
storage tanks are typically maintained at differing pressures so that
initial filling is done at the lowest pressure and final topping off is
done at the highest pressure. This cascaded fill approach minimizes
energy required to fill a vehicle CNG fuel tank. Compressor 806 controls
the pressure in tanks 805 via sequencing valves 808 when valve 809 is
open. All valves and flow meter 804 are electronically controlled so that
the amount of CNG dispensed at each filling post is precisely known. This
configuration eliminates the need for a separate expensive flow meter at
each filling post 801. Flow meter 804 can dispense CNG at a rate in the
range of about 5 DGE per minute to about 100 DGE per minute, depending on
the number of CNG filling posts 801. It is noted that the CNG fueling
area may be paved or unpaved as there is no ground spillage from a CNG
fuel dispensing facility. As can be appreciated, this dispensing system
can be used for any fuel whether it is gaseous or liquid. The principal
innovation is the use of a single flow meter to dispense fuel to multiple
fueling stations. All the valves, the single flow meter and storage tanks
can be contained in a single nearby or remote location with an
underground natural gas line routed to the area of the various gas
filling posts.

Economics of Multi-Fuel Vehicles

[0166] As can be appreciated, the price of fuels can vary over time as
well as with the type of fueling station. FIG. 9 shows typical annual
price variation of diesel and compressed natural gas fuels. In recent
years, the price of compressed natural gas has been less than that of
diesel when compared on a specific energy basis. The price of compressed
natural gas is expressed in Diesel Gallon Equivalents (DGEs) where a DGE
of natural gas delivers the same energy as a gallon of diesel on a low
heat value (LHV) basis. For the early part of the year from April 2008 to
March 2009, the price of diesel was roughly twice that of CNG. For the
latter part of the year, the price of diesel was only slightly higher
than that of CNG. As can be appreciated the price of diesel can, at
times, be lower than the price of CNG.

[0167] Another advantage of multi-fuel capability is that the risk from
severe price spikes due to temporary supply and demand issues with a
particular fuel can be mitigated or eliminated.

[0168] FIG. 10 shows typical variation of price as a function of station
size. This shows the price of diesel and natural gas as a function of
fueling station type and size for March 2009 when the price of diesel was
roughly twice that of CNG. At this time, the price of LNG was somewhat
less than the price of diesel while the price of CNG purchased at a large
private fueling station was roughly half the price of diesel. It is noted
that the cost and price of CNG is almost always lower than the cost and
price of LNG.

[0169]FIG. 11 shows breakeven cost for use of a lower price alternate
fuel. This figure illustrates an example of a Class 8 long-haul truck
capable of operating on either diesel or CNG fuel. The diesel tank
capacity is 300 gallons and the auxiliary CNG tanks have a capacity of 60
DGEs. Under reasonable driving assumptions, the analysis evaluates the
price spread required between diesel and CNG (when CNG is less expensive
than diesel) to recover the capital cost of the CNG tanks in 3 years.
When a DGE of CNG is 48 cents less than the price of a gallon of diesel
in this example, breakeven occurs in 3 years. When the price differential
of a DGE of CNG is greater than 48 cents compared to the price of a
gallon of diesel, there is a net profit realized from using CNG in less
than 3 years. Alternately, when the price differential of a DGE of CNG is
less than 48 cents compared to the price of a gallon of diesel, it will
take longer than 3 years to breakeven.

[0170] This analysis shows how a multi-fuel strategy can be developed
based on projections of fuel costs and/or fuel consumption. If diesel
fuel is less expensive than CNG, for example, then the auxiliary tanks
can be removed from the truck to save weight. If diesel fuel is more
expensive than CNG, then the truck can be operated as much as possible on
CNG. If CNG is not available, then the truck can be operated on diesel.
In any of these situations, the vehicle operator is not bound by the
auxiliary fuel infrastructure. However, as the fuel infrastructure grows,
the vehicle operator can take more frequent advantage of the lower cost
fuel.

Optimizing Fuel Usage and Driving Strategy

[0171]FIG. 12 is a schematic representation of a network-based system for
optimizing fuel consumption and driving strategy for a multi-fuel
vehicle. With a multi-fuel vehicle of the present invention, the operator
always has the option of running on a widely available fuel such as
diesel or gasoline which has a well-developed fuel dispensing
infrastructure and to which the operator is accustomed. However, the
operator has an opportunity to substantially reduce vehicle operating
costs and/or fuel consumption by utilizing a Wide Area Network (WAN),
such as the Internet, to optimize fuel costs, fuel consumption and
driving schedule, especially with a vehicle that can operate on more than
one fuel. This opportunity arises because of 1) the ability of a gas
turbine engine to readily burn multiple fuels or combinations of multiple
fuels and 2) the ability of the operator to switch fuels on the fly
(while driving). This first ability, in turn, arises because the gas
turbine engine burns fuels continuously based on their energy content,
not cyclically based on their ignition characteristics as is the case
with reciprocating engines such as diesel engines.

[0172] As shown in FIG. 12, the system includes a vehicle 1206, a
satellite positioning system 1202, a navigation information service 1203,
an optional dispatch capability 1204 and a first, second, and up to an
m-th fuel dispenser 1205a, 1205b, . . . 1205m, all interconnected by a
Wide Area Network (WAN) 1201.

[0174] The engine 1209 and fuel tanks 1207a through 1207n are apparatuses
having an operation or feature controlled by computer 1210. Computer 1210
includes a memory module and a processor module. The computer 1210 is
preferably a software-controlled device that includes a number of modules
in memory executable by the processor.

[0175] The executable modules include a controller to receive and process
status signals from the engine and fuel tanks and to generate and
transmit appropriate commands to the monitored engine and fuel tanks The
executable modules also include a computational module to receive and
process status signals from the engine, fuel tanks, satellite positioning
module, user or operator interface (which may be touchscreen, keyboard,
switch, computer, or other type of interface), fuel dispenser database
and WAN and which computes fuel and fueling recommendations and
recommended driving strategies to optimize fuel and other operational
costs. The executable modules also include a video display module (which
may be part of the user or operator interface) that allows the vehicle
operator to view the recommended fuel, fueling and driving strategies and
to select none, some or all of the recommendations or alternately to
instruct the computer to automatically select some or all of the
recommendations.

[0176] In one configuration, the executable modules include a fuel
monitoring module that receives the identities and monitors the remaining
amounts of the fuels or fuel mixtures in each of the first, second, . . .
n-th fuel tanks 1207a-n. The fuel monitoring module can receive the
identities of the fuels or fuel mixtures by any suitable technique, such
as by user or operator input via the user or operator interface, wireless
communication (by a suitable wireless data transmission protocol such as
by Bluetooth) from the fuel provider, a sensor or reader in signal
communication with an identification tag (such as RFID tag, bar code, and
the like) associated with the particular fuel dispenser dispensing fuel
into the corresponding fuel tank, Internet transmission via WAN 1202 from
the fuel provider, and the like.

[0177] In one configuration, the executable modules include a fuel
dispenser module to select a particular fuel type and/or mixture from one
or more fuel tanks and configure the engine and/or engine sub-component,
particularly a gas turbine or fuel injection system, to dispense and
combust the fuel. This normally requires one or more engine and/or engine
sub-component settings to be changed from a first setting associated with
a first fuel and/or fuel mixture to a second setting associated with a
second fuel and/or fuel mixture. This can be done, for example, using a
lookup table in the fuel dispenser database or an appropriate algorithm.
In the context of a gas turbine, the change of fuels and/or fuel mixtures
typically requires a change in the injection system and/or injected
fuel/air mixture.

[0178] The fuel dispensers 1205a through 1205m are fuel providers, such as
a privately or publically owned fueling stations, that are operable to
dispense various fuels. Fuel dispensers 1205a through 1205m also have
network sites which provide information on fuels, including price,
availability and subsidy (if available) information. The systems are
operable to provide, via WAN 1202, fuel dispenser information to any
vehicle 1206 which is connected to the WAN and which has on-board
capability to receive and process this information. The fuel dispenser
platforms can be any processor-based system, such as a mainframe,
personal computer, cell-phone, laptop or notebook computer.

[0179] The satellite positioning system 1202, navigation information
service 1203 (which may also include information on current road and
weather conditions) and fuel dispensers 1205a through 1205m sense and
collect parameters regarding fueling locations, directions to these
locations, available fuel types and specifications, fuel prices and
availability as well as any applicable subsidy information via the WAN
1201. The sensed parameters also include additional information such as,
for example, fuel ignition characteristics and fuel energy content and
the like.

[0180] The vehicle includes a number of sub-components. An on-board
computer has a memory and processor. Included in the memory are several
modules such as a controller, a computational module, and a display
module. Computer 1210 also has access to a fuel dispenser database 1213
which stores past information received from fuel dispensers via WAN 1201
or other sources as well as storing current information received from
fuel dispensers via WAN 1201 or other sources. As will be appreciated,
the database and memory can be any suitable non-transitory computer
readable medium.

[0181] In operation, on-board computer 1210 has access to the vehicle's
current location from on-board satellite positioning module 1212. The
on-board satellite positioning module 1212 may be a stand alone unit, a
part of a cell phone or a part of a portable computer connected to the
on-board computer 1210. Computer 1210 also has the ability to select from
any one of a number of fuels 1207a through 1207n carried on-board the
vehicle and to switch the vehicle's engine 1209 to operate on a selected
fuel. The selection of the fuel or fuel mixture is determined by the
particular fuel strategy, which can depend on a number of factors,
including desired emission characteristics (which can be dependent on the
physical location of the vehicle 1206), fuel availability (on board the
vehicle and/or in spatial proximity to the vehicle), fuel cost and/or
fuel consumption, and the like. Desired emission characteristics, for
example, can be stipulated by a governmental entity and can therefore
vary by sensed physical location. A city or first state, for instance,
can have a first set of emission requirements while a rural community or
different second state has no or a less restrictive, second set of
emission requirements. When the vehicle 1206 is in the city or first
state, it consumes a, typically more expensive but emissions compliant
fuel or fuel mixture, and, when the vehicle 1206 is in the rural
community or second state, it consumes a less expensive and less
emissions compliant fuel or fuel mixture.

[0182] The vehicle 1206 also includes an ability to automatically connect
to and interact with WAN 1201 via modem 1211. WAN 1201 includes
interconnections to satellite positioning system 1202 and a navigation
information service 1203. Satellite positioning system 1202 and a
navigation information service 1203 together provide the vehicle with
information on its location and on all routes available to the vehicle on
any selected map scale. WAN 1201 also includes interconnections to fuel
dispensers 1205a through 1205m along the routes within at least several
hours driving range of the vehicle. WAN 1201 optionally includes
connection to the vehicle owner dispatch center 1204 if the vehicle is
part of a fleet.

[0183] The controller module in computer 1210 continuously monitors the
amount of each of the fuels on board as well as the current fuel in use
and the current fuel consumption of engine 1209. In one configuration,
the controller module further monitors the current (average, median,
mode, lowest, and/or highest) price (which monitoring function can be
limited to the prevailing price in the physical vicinity of the vehicle)
of the various fuels in the first, second, . . . n-th fuel tanks The
controller module also continuously monitors satellite positioning module
1211 to determine where the vehicle is currently located. The
computational module receives information from the controller module and
continuously calculates vehicle range for each fuel, the maximum range of
the vehicle for all combinations of fuel and the driving distance and
time to each of the fuel dispensers within driving range. The display
module continuously displays this information on a video monitor
accessible to the operator.

[0185] WAN 1201 for fuel dispenser information obtained from fuel
dispenser websites 1205a through 1205m. This information includes
location of the fuel dispenser, availability and prices of the various
fuels offered, the hours of business and any other pertinent information
such as other products and amenities offered. The controller also
continuously interrogates WAN 1201 for information on vehicle location by
interrogating satellite positioning system 1202 and navigation
information service 1203.

[0186] From this information, the computational module, in one
configuration, estimates the best locations for the operator to obtain
the fuels of interest based on fuel prices and the distance to the fuel
dispenser, and the video module arranges this information for display on
the operator's video monitor. This estimation can be done in many ways.
In one technique, the computational module determines the amount of fuel
needed to fill the particular fuel tank and, for that fuel, determines
the total cost, for each fuel provider, to fill the tank. The module can
also determine the fuel cost and/or fuel consumption to drive to that
fuel provider. A total cost (including both the fuel cost to fill the
particular fuel tank and fuel cost and/or fuel consumption to drive to
that fuel provider (using in the latter calculation a current or historic
fuel cost) can be determined for each fuel provider. The fuel provider
having the lowest total cost would be the first recommendation, the fuel
provider having the next lowest total cost the second, and so on. This
computation can be done for each type of on board fuel or a subset of the
fuels. In the former case, the total cost for each provider would be
based on the total fuel costs to fill each fuel tank plus the fuel cost
and/or fuel consumption to drive to the provider. Other algorithms may be
employed as will be appreciated by one of ordinary skill in the art.

[0187] In one configuration, the computational module selects and
implements an appropriate fuel strategy. The fuel strategy can be based,
for example, on proximity to a particular type of fuel provider, emission
requirement, on board relative fuel costs and/or fuel consumption of the
fuels in the various fuel tanks, characteristics of to driving route and
the like.

[0188] In one configuration, the operator can then select the best, or
recommended, option for refueling or the operator can instruct computer
1210 to automatically select the best option for refueling. If the
vehicle is part of a fleet, computer 1210 can communicate the collected
information and recommended options via WAN 1201 to the fleet dispatcher
1204 for further advice and consent.

[0189] In one configuration, the computational module selects and
recommends to the operator a particular fuel strategy or the operator can
instruct the computer 1210 to automatically select the best fuel
strategy. implements an appropriate fuel strategy. If the vehicle is part
of a fleet, computer 1210 can communicate the collected information and
recommended fuel strategy via WAN 1201 to the fleet dispatcher 1204 for
further advice and consent.

[0190] The on board logic may also have a built in payment capability to
handle credit card payments, prepaid amounts, or it may just capture
expenditures. This will reduce the actions required by the driver at the
truck stop. Additionally, the fuel dispenser may be configured to send
out a message to the drivers cell phone when fueling is completed or
about to be completed. Other information can be incorporated such as
maintenance, efficiency, payload for ton-mile calculations. Built in load
cells for calculation might become a necessity for new efficiency
legislation. The data collected could provide a detailed report that
would allow monitoring of key metrics.

[0191] An operational embodiment of the system of FIG. 12 will now be
described with reference to FIG. 13. In step 1300, the computer 1210
(e.g., using various executable modules including the fuel monitoring
module, computational module, and/or controller module) determines
current on board fuel and engine information. Fuel information includes,
for example, the type and amount of fuel in each first, second, . . .
n-th fuel tank 1207a-n, which fuel(s) is/are currently being fed into the
engine 1209, and the current fuel consumption rate (based on a measure of
miles traveled (e.g., miles/gallon), time (e.g., gallons/hour), and the
like), and current injection fuel mixture (e.g., fuel type and fuel/air
ratio) being fed to the engine 1209. Engine information includes, for
example, current engine temperature, current engine air and fuel flow
rates, current engine oil pressure, current vehicle velocity and/or
acceleration, current engine power output, and the like).

[0192] In step 1304, the computer 1210 (e.g., using the satellite
positioning module and/or computational module) determines the current
vehicle location. Vehicle location is commonly relative to a coordinate
system, such as the Global Positioning System.

[0193] In step 1308, the computer 1210 (accessing the fuel dispenser
database 1213 and/or using the computational module and/or controller
module) determines, by on-board fuel type, fuel and pricing information
within a determined range of the vehicle. Fuel and pricing information
includes, for example, current (average, median, mode, lowest, and/or
highest) price, identity and location of each first, second, . . . m-th
fuel dispenser 1205a-m, hours of business and products and amenities
offered of each first, second, . . . m-th fuel dispenser 1205a-m, for
each fuel dispenser the available fuel types and fuel replacement cost
(e.g., the cost to fill the corresponding first, second, . . . nth fuel
tank 1207a-n, which can include the fuel cost to drive from the current
vehicle location to the fuel dispenser), directions from the current
vehicle location to each first, second, . . . m-th fuel dispenser
1205a-m, link to web page of each first, second, . . . m-th fuel
dispenser 1205a-m, and the like.

[0194] In optional step 1312, the computer 1210 determines, based on the
current physical location of the vehicle and using a lookup table, any
pertinent emissions requirements or regulations to be complied with by
the vehicle. The lookup table may express the emissions requirements in
terms of the fuel injection mixture to be employed.

[0195] In optional step 1316, the computer 1210 determines any operator
input received regarding the fuel strategy or information desired. Input
can include, for example, operator preferences and configuration
commands, requests for specific type of information or other output from
the computer 1210, and the like.

[0196] In step 1320, the computer 1210 (using the controller module,
computational module, and/or fuel dispenser module) determines an
appropriate fuel strategy to be implemented and/or presented to the
operator for his or her consideration. The fuel strategy, as noted above,
can be a recommendation of a refueling location, a particular fuel type
and/or fuel mixture to be employed (in response to fuel type availability
and/or unavailability, emission requirements, fuel costs, and the like).

[0197] In optional step 1324, the selected or determined fuel strategy is
presented to the operator, by the user interface and/or video display
module. The operator, in response, can select or approve a recommended
strategy.

[0198] In step 1328, the fuel strategy is implemented by the computer 1210
(using the controller module and/or fuel dispenser module). As noted,
implementation includes selecting a particular fuel type and/or fuel
mixture and configuring the engine and/or an engine sub-component to
dispense and combust the fuel.

[0199] As will be appreciated, the above steps can be performed in any
order or sequence.

[0200] The system disclosed in FIGS. 12 and 13 allow the operator of the
vehicle, or the fleet manager if the vehicle is a member of a fleet, to
optimize operational costs and/or fuel consumption by estimating the best
combination of fuels, fuel dispensers and driving and/or fuel strategies.
By carrying at least one readily available fuel (such as diesel or
gasoline), the operator is free of infrastructure shortcomings for other
fuels that may be less expensive or have desirable emission
characteristics. With the assistance of the system of FIG. 12, the
vehicle operator can therefore efficiently manage the use of on-board
fuels as well as efficiently manage his driving schedule and route to
continue to get the best fuels at the best available prices.

[0201] A number of variations and modifications of the inventions can be
used. As will be appreciated, it would be possible to provide for some
features of the inventions without providing others.

[0202] The present invention, in various embodiments, includes components,
methods, processes, systems and/or apparatus substantially as depicted
and described herein, including various embodiments, sub-combinations,
and subsets thereof. Those of skill in the art will understand how to
make and use the present invention after understanding the present
disclosure. The present invention, in various embodiments, includes
providing devices and processes in the absence of items not depicted
and/or described herein or in various embodiments hereof, including in
the absence of such items as may have been used in previous devices or
processes, for example for improving performance, achieving ease and/or
reducing cost of implementation.

[0203] The foregoing discussion of the invention has been presented for
purposes of illustration and description. The foregoing is not intended
to limit the invention to the form or forms disclosed herein. In the
foregoing Detailed Description for example, various features of the
invention are grouped together in one or more embodiments for the purpose
of streamlining the disclosure. This method of disclosure is not to be
interpreted as reflecting an intention that the claimed invention
requires more features than are expressly recited in each claim. Rather,
as the following claims reflect, inventive aspects lie in less than all
features of a single foregoing disclosed embodiment. Thus, the following
claims are hereby incorporated into this Detailed Description, with each
claim standing on its own as a separate preferred embodiment of the
invention.

[0204] Moreover though the description of the invention has included
description of one or more embodiments and certain variations and
modifications, other variations and modifications are within the scope of
the invention, e.g., as may be within the skill and knowledge of those in
the art, after understanding the present disclosure. It is intended to
obtain rights which include alternative embodiments to the extent
permitted, including alternate, interchangeable and/or equivalent
structures, functions, ranges or steps to those claimed, whether or not
such alternate, interchangeable and/or equivalent structures, functions,
ranges or steps are disclosed herein, and without intending to publicly
dedicate any patentable subject matter.

Patent applications by David William Dewis, North Hampton, NH US

Patent applications by Douglas W. Swartz, Lakewood, CO US

Patent applications by Frank Wegner Donnelly, North Vancouver CA

Patent applications by ICR TURBINE ENGINE CORPORATION

Patent applications in class With indicator or control of power plant (e.g., performance)

Patent applications in all subclasses With indicator or control of power plant (e.g., performance)